#define _CRT_SECURE_NO_WARNINGS 1
#include <iostream>
#include <vector>

using namespace std;

class Solution
{
public:
    int minCostClimbingStairs(vector<int>& cost)
    {
        int n = cost.size();
        vector<int> dp(n + 1);
        for (int i = 2; i <= n; i++)
            dp[i] = min(dp[i - 1] + cost[i - 1], dp[i - 2] + cost[i - 2]);
        return dp[n];
    }
};

class Solution
{
public:
    int minCostClimbingStairs(vector<int>& cost)
    {
        int n = cost.size();
        vector<int> dp(n);
        dp[n - 1] = cost[n - 1], dp[n - 2] = cost[n - 2];
        for (int i = n - 3; i >= 0; i--)
        {
            dp[i] = min(dp[i + 1] + cost[i], dp[i + 2] + cost[i]);
        }
        return min(dp[0], dp[1]);
    }
};